Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Light emitting element

a technology of light-emitting elements and light-emitting devices, which is applied in the direction of discharge tubes/lamp details, discharge tubes/lamp details, luminescent compositions, etc., can solve the problems of low light-emitting efficiency and lower efficiency of light-emitting devices, and achieve high-efficiency light-emitting, facilitate light-emitting, and increase light-emitting efficiency

Active Publication Date: 2012-05-15
PANASONIC CORP
View PDF23 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

"The present invention provides a light emitting device with high light emission efficiency. The device includes phosphor particles with improved light emitting efficiency. The phosphor particles have an n-type nitride semiconductor part and a p-type nitride semiconductor part with a wurtzite-type crystal structure and c axes parallel with each other. The phosphor particles are placed between electrodes and can have an electric current path in a direction perpendicular to the c axis. The insulation layer on the phosphor particles prevents electric current from flowing through the particles and ensures high-efficiency light emission. The device has a high area and is suitable for use in various applications."

Problems solved by technology

However, even when an electroluminescent device is fabricated using phosphor particles according to the conventional technique described in the Patent Document 1, there is the problem of a low light emitting efficiency.
The other one of them is that the conventional technique can not restrict the electric current paths within the phosphor particles, which causes mixture of two electric current paths, which are an electric current path with a lower light emission efficiency and an electric current path with a higher light emission efficiency, thereby resulting in a lower efficiency of the light emitting device.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Light emitting element
  • Light emitting element
  • Light emitting element

Examples

Experimental program
Comparison scheme
Effect test

first embodiment

(First Embodiment)

[0052]FIG. 1 is a cross-sectional view schematically illustrating the structure of a light emitting device 70 according to the present first embodiment. In the light emitting device 70, on a lower substrate 10, there are placed a lower electrode 20, phosphor particles 50, an upper electrode 30, and an upper substrate 40, in the mentioned order. In the light emitting device 70, the plurality of phosphor particles 50 placed between the lower electrode 20 and the upper electrode 30 form a phosphor layer. Further, FIG. 1 illustrates a minimum structure necessary for light emission, and other members may be provided in addition thereto.

[0053]FIG. 2 is a cross-sectional view illustrating the cross-sectional structure of a phosphor particle 50 taken along the direction of the c axis thereof. FIG. 3 is a cross-sectional view illustrating the cross-sectional structure of the phosphor particle 50 taken along a plane perpendicular to the c axis thereof. In the light emitting ...

first example

[0077]Hereinafter, there will be described a method for fabricating a light emitting device according to the first example. In this case, at first, phosphor particles were formed, and the resultant phosphor particles were sandwiched between electrodes to form a light emitting device.

[0078](a) A sapphire substrate having a surface orientation of (0,0,0,1) and having a diameter of 5.08 cm (2 inches) was employed as a growth substrate 61. An SiO2 film with a thickness of 5 micrometers was formed as a growth mask 62 on the sapphire substrate 61 through a formation mask, through sputtering. It was formed through sputtering, using a SiO2 target as a target, in an atmosphere of an Ar gas. The growth mask 62 had hole portions with a diameter of 3 micrometers.

[0079](b) An AlN film was formed as nucleuses 51 thereon through sputtering. It was formed through sputtering, using an Al target as a target, in an atmosphere of an N2 gas. The AlN was grown in the direction of the c axis to have a thi...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

A light emitting device includes a pair of electrodes facing to each other and a phosphor layer which is sandwiched between the pair of electrodes and includes phosphor particles placed therein. The phosphor particles include an n-type nitride semiconductor part and a p-type nitride semiconductor part, the n-type nitride semiconductor part and the p-type nitride semiconductor part are made of respective single crystals having wurtzite-type crystal structures having c axes parallel with each other, and the phosphor particles include an insulation layer provided to overlie one end surface out of their end surfaces perpendicular to the c axes.

Description

RELATED APPLICATIONS[0001]This application is the U.S. National Phase under 35 U.S.C. §371 of International Application No. PCT / JP2009 / 000785, filed on Feb. 24, 2009, which in turn claims the benefit of Japanese Application No. 2008-054725, filed on Mar. 5, 2008, the disclosures of which Applications are incorporated by reference herein.BACKGROUND[0002]1. Technical Field[0003]The present invention relates to a light emitting element / device which is operated by a direct voltage applied thereto.[0004]2. Background Art[0005]Attention has been focused on nitride semiconductors, as practical semiconductor materials for use in light emitting devices, particularly blue-LEDs; blue light emitting diodes and UV-LEDs; Ultra-violet light emitting diodes, among light emitting devices which are operated by application of direct currents thereto. Particularly, attention has been focused on GaN based semiconductors which are represented by gallium nitride (GaN), indium gallium nitride (InGaN) mixed...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Patents(United States)
IPC IPC(8): H01L33/32H01L33/24
CPCC09K11/025H01L33/24H01L33/08C09K11/642
Inventor SHIMAMURA, TAKAYUKIONO, MASAYUKITANIGUCHI, REIKOSATOH, EIICHIMURAYAMA, MASATOODAGIRI, MASARU
Owner PANASONIC CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com